diff options
Diffstat (limited to 'utils/zenutils/libraries/zlib123/zlib/trees.c')
-rw-r--r--[-rwxr-xr-x] | utils/zenutils/libraries/zlib123/zlib/trees.c | 2438 |
1 files changed, 1219 insertions, 1219 deletions
diff --git a/utils/zenutils/libraries/zlib123/zlib/trees.c b/utils/zenutils/libraries/zlib123/zlib/trees.c index 7a04802862..395e4e1681 100755..100644 --- a/utils/zenutils/libraries/zlib123/zlib/trees.c +++ b/utils/zenutils/libraries/zlib123/zlib/trees.c | |||
@@ -1,1219 +1,1219 @@ | |||
1 | /* trees.c -- output deflated data using Huffman coding | 1 | /* trees.c -- output deflated data using Huffman coding |
2 | * Copyright (C) 1995-2005 Jean-loup Gailly | 2 | * Copyright (C) 1995-2005 Jean-loup Gailly |
3 | * For conditions of distribution and use, see copyright notice in zlib.h | 3 | * For conditions of distribution and use, see copyright notice in zlib.h |
4 | */ | 4 | */ |
5 | 5 | ||
6 | /* | 6 | /* |
7 | * ALGORITHM | 7 | * ALGORITHM |
8 | * | 8 | * |
9 | * The "deflation" process uses several Huffman trees. The more | 9 | * The "deflation" process uses several Huffman trees. The more |
10 | * common source values are represented by shorter bit sequences. | 10 | * common source values are represented by shorter bit sequences. |
11 | * | 11 | * |
12 | * Each code tree is stored in a compressed form which is itself | 12 | * Each code tree is stored in a compressed form which is itself |
13 | * a Huffman encoding of the lengths of all the code strings (in | 13 | * a Huffman encoding of the lengths of all the code strings (in |
14 | * ascending order by source values). The actual code strings are | 14 | * ascending order by source values). The actual code strings are |
15 | * reconstructed from the lengths in the inflate process, as described | 15 | * reconstructed from the lengths in the inflate process, as described |
16 | * in the deflate specification. | 16 | * in the deflate specification. |
17 | * | 17 | * |
18 | * REFERENCES | 18 | * REFERENCES |
19 | * | 19 | * |
20 | * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". | 20 | * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". |
21 | * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc | 21 | * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc |
22 | * | 22 | * |
23 | * Storer, James A. | 23 | * Storer, James A. |
24 | * Data Compression: Methods and Theory, pp. 49-50. | 24 | * Data Compression: Methods and Theory, pp. 49-50. |
25 | * Computer Science Press, 1988. ISBN 0-7167-8156-5. | 25 | * Computer Science Press, 1988. ISBN 0-7167-8156-5. |
26 | * | 26 | * |
27 | * Sedgewick, R. | 27 | * Sedgewick, R. |
28 | * Algorithms, p290. | 28 | * Algorithms, p290. |
29 | * Addison-Wesley, 1983. ISBN 0-201-06672-6. | 29 | * Addison-Wesley, 1983. ISBN 0-201-06672-6. |
30 | */ | 30 | */ |
31 | 31 | ||
32 | /* @(#) $Id$ */ | 32 | /* @(#) $Id$ */ |
33 | 33 | ||
34 | /* #define GEN_TREES_H */ | 34 | /* #define GEN_TREES_H */ |
35 | 35 | ||
36 | #include "deflate.h" | 36 | #include "deflate.h" |
37 | 37 | ||
38 | #ifdef DEBUG | 38 | #ifdef DEBUG |
39 | # include <ctype.h> | 39 | # include <ctype.h> |
40 | #endif | 40 | #endif |
41 | 41 | ||
42 | /* =========================================================================== | 42 | /* =========================================================================== |
43 | * Constants | 43 | * Constants |
44 | */ | 44 | */ |
45 | 45 | ||
46 | #define MAX_BL_BITS 7 | 46 | #define MAX_BL_BITS 7 |
47 | /* Bit length codes must not exceed MAX_BL_BITS bits */ | 47 | /* Bit length codes must not exceed MAX_BL_BITS bits */ |
48 | 48 | ||
49 | #define END_BLOCK 256 | 49 | #define END_BLOCK 256 |
50 | /* end of block literal code */ | 50 | /* end of block literal code */ |
51 | 51 | ||
52 | #define REP_3_6 16 | 52 | #define REP_3_6 16 |
53 | /* repeat previous bit length 3-6 times (2 bits of repeat count) */ | 53 | /* repeat previous bit length 3-6 times (2 bits of repeat count) */ |
54 | 54 | ||
55 | #define REPZ_3_10 17 | 55 | #define REPZ_3_10 17 |
56 | /* repeat a zero length 3-10 times (3 bits of repeat count) */ | 56 | /* repeat a zero length 3-10 times (3 bits of repeat count) */ |
57 | 57 | ||
58 | #define REPZ_11_138 18 | 58 | #define REPZ_11_138 18 |
59 | /* repeat a zero length 11-138 times (7 bits of repeat count) */ | 59 | /* repeat a zero length 11-138 times (7 bits of repeat count) */ |
60 | 60 | ||
61 | local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ | 61 | local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ |
62 | = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0}; | 62 | = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0}; |
63 | 63 | ||
64 | local const int extra_dbits[D_CODES] /* extra bits for each distance code */ | 64 | local const int extra_dbits[D_CODES] /* extra bits for each distance code */ |
65 | = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13}; | 65 | = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13}; |
66 | 66 | ||
67 | local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */ | 67 | local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */ |
68 | = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; | 68 | = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; |
69 | 69 | ||
70 | local const uch bl_order[BL_CODES] | 70 | local const uch bl_order[BL_CODES] |
71 | = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; | 71 | = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; |
72 | /* The lengths of the bit length codes are sent in order of decreasing | 72 | /* The lengths of the bit length codes are sent in order of decreasing |
73 | * probability, to avoid transmitting the lengths for unused bit length codes. | 73 | * probability, to avoid transmitting the lengths for unused bit length codes. |
74 | */ | 74 | */ |
75 | 75 | ||
76 | #define Buf_size (8 * 2*sizeof(char)) | 76 | #define Buf_size (8 * 2*sizeof(char)) |
77 | /* Number of bits used within bi_buf. (bi_buf might be implemented on | 77 | /* Number of bits used within bi_buf. (bi_buf might be implemented on |
78 | * more than 16 bits on some systems.) | 78 | * more than 16 bits on some systems.) |
79 | */ | 79 | */ |
80 | 80 | ||
81 | /* =========================================================================== | 81 | /* =========================================================================== |
82 | * Local data. These are initialized only once. | 82 | * Local data. These are initialized only once. |
83 | */ | 83 | */ |
84 | 84 | ||
85 | #define DIST_CODE_LEN 512 /* see definition of array dist_code below */ | 85 | #define DIST_CODE_LEN 512 /* see definition of array dist_code below */ |
86 | 86 | ||
87 | #if defined(GEN_TREES_H) || !defined(STDC) | 87 | #if defined(GEN_TREES_H) || !defined(STDC) |
88 | /* non ANSI compilers may not accept trees.h */ | 88 | /* non ANSI compilers may not accept trees.h */ |
89 | 89 | ||
90 | local ct_data static_ltree[L_CODES+2]; | 90 | local ct_data static_ltree[L_CODES+2]; |
91 | /* The static literal tree. Since the bit lengths are imposed, there is no | 91 | /* The static literal tree. Since the bit lengths are imposed, there is no |
92 | * need for the L_CODES extra codes used during heap construction. However | 92 | * need for the L_CODES extra codes used during heap construction. However |
93 | * The codes 286 and 287 are needed to build a canonical tree (see _tr_init | 93 | * The codes 286 and 287 are needed to build a canonical tree (see _tr_init |
94 | * below). | 94 | * below). |
95 | */ | 95 | */ |
96 | 96 | ||
97 | local ct_data static_dtree[D_CODES]; | 97 | local ct_data static_dtree[D_CODES]; |
98 | /* The static distance tree. (Actually a trivial tree since all codes use | 98 | /* The static distance tree. (Actually a trivial tree since all codes use |
99 | * 5 bits.) | 99 | * 5 bits.) |
100 | */ | 100 | */ |
101 | 101 | ||
102 | uch _dist_code[DIST_CODE_LEN]; | 102 | uch _dist_code[DIST_CODE_LEN]; |
103 | /* Distance codes. The first 256 values correspond to the distances | 103 | /* Distance codes. The first 256 values correspond to the distances |
104 | * 3 .. 258, the last 256 values correspond to the top 8 bits of | 104 | * 3 .. 258, the last 256 values correspond to the top 8 bits of |
105 | * the 15 bit distances. | 105 | * the 15 bit distances. |
106 | */ | 106 | */ |
107 | 107 | ||
108 | uch _length_code[MAX_MATCH-MIN_MATCH+1]; | 108 | uch _length_code[MAX_MATCH-MIN_MATCH+1]; |
109 | /* length code for each normalized match length (0 == MIN_MATCH) */ | 109 | /* length code for each normalized match length (0 == MIN_MATCH) */ |
110 | 110 | ||
111 | local int base_length[LENGTH_CODES]; | 111 | local int base_length[LENGTH_CODES]; |
112 | /* First normalized length for each code (0 = MIN_MATCH) */ | 112 | /* First normalized length for each code (0 = MIN_MATCH) */ |
113 | 113 | ||
114 | local int base_dist[D_CODES]; | 114 | local int base_dist[D_CODES]; |
115 | /* First normalized distance for each code (0 = distance of 1) */ | 115 | /* First normalized distance for each code (0 = distance of 1) */ |
116 | 116 | ||
117 | #else | 117 | #else |
118 | # include "trees.h" | 118 | # include "trees.h" |
119 | #endif /* GEN_TREES_H */ | 119 | #endif /* GEN_TREES_H */ |
120 | 120 | ||
121 | struct static_tree_desc_s { | 121 | struct static_tree_desc_s { |
122 | const ct_data *static_tree; /* static tree or NULL */ | 122 | const ct_data *static_tree; /* static tree or NULL */ |
123 | const intf *extra_bits; /* extra bits for each code or NULL */ | 123 | const intf *extra_bits; /* extra bits for each code or NULL */ |
124 | int extra_base; /* base index for extra_bits */ | 124 | int extra_base; /* base index for extra_bits */ |
125 | int elems; /* max number of elements in the tree */ | 125 | int elems; /* max number of elements in the tree */ |
126 | int max_length; /* max bit length for the codes */ | 126 | int max_length; /* max bit length for the codes */ |
127 | }; | 127 | }; |
128 | 128 | ||
129 | local static_tree_desc static_l_desc = | 129 | local static_tree_desc static_l_desc = |
130 | {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; | 130 | {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; |
131 | 131 | ||
132 | local static_tree_desc static_d_desc = | 132 | local static_tree_desc static_d_desc = |
133 | {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; | 133 | {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; |
134 | 134 | ||
135 | local static_tree_desc static_bl_desc = | 135 | local static_tree_desc static_bl_desc = |
136 | {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; | 136 | {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; |
137 | 137 | ||
138 | /* =========================================================================== | 138 | /* =========================================================================== |
139 | * Local (static) routines in this file. | 139 | * Local (static) routines in this file. |
140 | */ | 140 | */ |
141 | 141 | ||
142 | local void tr_static_init OF((void)); | 142 | local void tr_static_init OF((void)); |
143 | local void init_block OF((deflate_state *s)); | 143 | local void init_block OF((deflate_state *s)); |
144 | local void pqdownheap OF((deflate_state *s, ct_data *tree, int k)); | 144 | local void pqdownheap OF((deflate_state *s, ct_data *tree, int k)); |
145 | local void gen_bitlen OF((deflate_state *s, tree_desc *desc)); | 145 | local void gen_bitlen OF((deflate_state *s, tree_desc *desc)); |
146 | local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count)); | 146 | local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count)); |
147 | local void build_tree OF((deflate_state *s, tree_desc *desc)); | 147 | local void build_tree OF((deflate_state *s, tree_desc *desc)); |
148 | local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code)); | 148 | local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code)); |
149 | local void send_tree OF((deflate_state *s, ct_data *tree, int max_code)); | 149 | local void send_tree OF((deflate_state *s, ct_data *tree, int max_code)); |
150 | local int build_bl_tree OF((deflate_state *s)); | 150 | local int build_bl_tree OF((deflate_state *s)); |
151 | local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes, | 151 | local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes, |
152 | int blcodes)); | 152 | int blcodes)); |
153 | local void compress_block OF((deflate_state *s, ct_data *ltree, | 153 | local void compress_block OF((deflate_state *s, ct_data *ltree, |
154 | ct_data *dtree)); | 154 | ct_data *dtree)); |
155 | local void set_data_type OF((deflate_state *s)); | 155 | local void set_data_type OF((deflate_state *s)); |
156 | local unsigned bi_reverse OF((unsigned value, int length)); | 156 | local unsigned bi_reverse OF((unsigned value, int length)); |
157 | local void bi_windup OF((deflate_state *s)); | 157 | local void bi_windup OF((deflate_state *s)); |
158 | local void bi_flush OF((deflate_state *s)); | 158 | local void bi_flush OF((deflate_state *s)); |
159 | local void copy_block OF((deflate_state *s, charf *buf, unsigned len, | 159 | local void copy_block OF((deflate_state *s, charf *buf, unsigned len, |
160 | int header)); | 160 | int header)); |
161 | 161 | ||
162 | #ifdef GEN_TREES_H | 162 | #ifdef GEN_TREES_H |
163 | local void gen_trees_header OF((void)); | 163 | local void gen_trees_header OF((void)); |
164 | #endif | 164 | #endif |
165 | 165 | ||
166 | #ifndef DEBUG | 166 | #ifndef DEBUG |
167 | # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) | 167 | # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) |
168 | /* Send a code of the given tree. c and tree must not have side effects */ | 168 | /* Send a code of the given tree. c and tree must not have side effects */ |
169 | 169 | ||
170 | #else /* DEBUG */ | 170 | #else /* DEBUG */ |
171 | # define send_code(s, c, tree) \ | 171 | # define send_code(s, c, tree) \ |
172 | { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \ | 172 | { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \ |
173 | send_bits(s, tree[c].Code, tree[c].Len); } | 173 | send_bits(s, tree[c].Code, tree[c].Len); } |
174 | #endif | 174 | #endif |
175 | 175 | ||
176 | /* =========================================================================== | 176 | /* =========================================================================== |
177 | * Output a short LSB first on the stream. | 177 | * Output a short LSB first on the stream. |
178 | * IN assertion: there is enough room in pendingBuf. | 178 | * IN assertion: there is enough room in pendingBuf. |
179 | */ | 179 | */ |
180 | #define put_short(s, w) { \ | 180 | #define put_short(s, w) { \ |
181 | put_byte(s, (uch)((w) & 0xff)); \ | 181 | put_byte(s, (uch)((w) & 0xff)); \ |
182 | put_byte(s, (uch)((ush)(w) >> 8)); \ | 182 | put_byte(s, (uch)((ush)(w) >> 8)); \ |
183 | } | 183 | } |
184 | 184 | ||
185 | /* =========================================================================== | 185 | /* =========================================================================== |
186 | * Send a value on a given number of bits. | 186 | * Send a value on a given number of bits. |
187 | * IN assertion: length <= 16 and value fits in length bits. | 187 | * IN assertion: length <= 16 and value fits in length bits. |
188 | */ | 188 | */ |
189 | #ifdef DEBUG | 189 | #ifdef DEBUG |
190 | local void send_bits OF((deflate_state *s, int value, int length)); | 190 | local void send_bits OF((deflate_state *s, int value, int length)); |
191 | 191 | ||
192 | local void send_bits(s, value, length) | 192 | local void send_bits(s, value, length) |
193 | deflate_state *s; | 193 | deflate_state *s; |
194 | int value; /* value to send */ | 194 | int value; /* value to send */ |
195 | int length; /* number of bits */ | 195 | int length; /* number of bits */ |
196 | { | 196 | { |
197 | Tracevv((stderr," l %2d v %4x ", length, value)); | 197 | Tracevv((stderr," l %2d v %4x ", length, value)); |
198 | Assert(length > 0 && length <= 15, "invalid length"); | 198 | Assert(length > 0 && length <= 15, "invalid length"); |
199 | s->bits_sent += (ulg)length; | 199 | s->bits_sent += (ulg)length; |
200 | 200 | ||
201 | /* If not enough room in bi_buf, use (valid) bits from bi_buf and | 201 | /* If not enough room in bi_buf, use (valid) bits from bi_buf and |
202 | * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) | 202 | * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) |
203 | * unused bits in value. | 203 | * unused bits in value. |
204 | */ | 204 | */ |
205 | if (s->bi_valid > (int)Buf_size - length) { | 205 | if (s->bi_valid > (int)Buf_size - length) { |
206 | s->bi_buf |= (value << s->bi_valid); | 206 | s->bi_buf |= (value << s->bi_valid); |
207 | put_short(s, s->bi_buf); | 207 | put_short(s, s->bi_buf); |
208 | s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); | 208 | s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); |
209 | s->bi_valid += length - Buf_size; | 209 | s->bi_valid += length - Buf_size; |
210 | } else { | 210 | } else { |
211 | s->bi_buf |= value << s->bi_valid; | 211 | s->bi_buf |= value << s->bi_valid; |
212 | s->bi_valid += length; | 212 | s->bi_valid += length; |
213 | } | 213 | } |
214 | } | 214 | } |
215 | #else /* !DEBUG */ | 215 | #else /* !DEBUG */ |
216 | 216 | ||
217 | #define send_bits(s, value, length) \ | 217 | #define send_bits(s, value, length) \ |
218 | { int len = length;\ | 218 | { int len = length;\ |
219 | if (s->bi_valid > (int)Buf_size - len) {\ | 219 | if (s->bi_valid > (int)Buf_size - len) {\ |
220 | int val = value;\ | 220 | int val = value;\ |
221 | s->bi_buf |= (val << s->bi_valid);\ | 221 | s->bi_buf |= (val << s->bi_valid);\ |
222 | put_short(s, s->bi_buf);\ | 222 | put_short(s, s->bi_buf);\ |
223 | s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ | 223 | s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ |
224 | s->bi_valid += len - Buf_size;\ | 224 | s->bi_valid += len - Buf_size;\ |
225 | } else {\ | 225 | } else {\ |
226 | s->bi_buf |= (value) << s->bi_valid;\ | 226 | s->bi_buf |= (value) << s->bi_valid;\ |
227 | s->bi_valid += len;\ | 227 | s->bi_valid += len;\ |
228 | }\ | 228 | }\ |
229 | } | 229 | } |
230 | #endif /* DEBUG */ | 230 | #endif /* DEBUG */ |
231 | 231 | ||
232 | 232 | ||
233 | /* the arguments must not have side effects */ | 233 | /* the arguments must not have side effects */ |
234 | 234 | ||
235 | /* =========================================================================== | 235 | /* =========================================================================== |
236 | * Initialize the various 'constant' tables. | 236 | * Initialize the various 'constant' tables. |
237 | */ | 237 | */ |
238 | local void tr_static_init() | 238 | local void tr_static_init() |
239 | { | 239 | { |
240 | #if defined(GEN_TREES_H) || !defined(STDC) | 240 | #if defined(GEN_TREES_H) || !defined(STDC) |
241 | static int static_init_done = 0; | 241 | static int static_init_done = 0; |
242 | int n; /* iterates over tree elements */ | 242 | int n; /* iterates over tree elements */ |
243 | int bits; /* bit counter */ | 243 | int bits; /* bit counter */ |
244 | int length; /* length value */ | 244 | int length; /* length value */ |
245 | int code; /* code value */ | 245 | int code; /* code value */ |
246 | int dist; /* distance index */ | 246 | int dist; /* distance index */ |
247 | ush bl_count[MAX_BITS+1]; | 247 | ush bl_count[MAX_BITS+1]; |
248 | /* number of codes at each bit length for an optimal tree */ | 248 | /* number of codes at each bit length for an optimal tree */ |
249 | 249 | ||
250 | if (static_init_done) return; | 250 | if (static_init_done) return; |
251 | 251 | ||
252 | /* For some embedded targets, global variables are not initialized: */ | 252 | /* For some embedded targets, global variables are not initialized: */ |
253 | static_l_desc.static_tree = static_ltree; | 253 | static_l_desc.static_tree = static_ltree; |
254 | static_l_desc.extra_bits = extra_lbits; | 254 | static_l_desc.extra_bits = extra_lbits; |
255 | static_d_desc.static_tree = static_dtree; | 255 | static_d_desc.static_tree = static_dtree; |
256 | static_d_desc.extra_bits = extra_dbits; | 256 | static_d_desc.extra_bits = extra_dbits; |
257 | static_bl_desc.extra_bits = extra_blbits; | 257 | static_bl_desc.extra_bits = extra_blbits; |
258 | 258 | ||
259 | /* Initialize the mapping length (0..255) -> length code (0..28) */ | 259 | /* Initialize the mapping length (0..255) -> length code (0..28) */ |
260 | length = 0; | 260 | length = 0; |
261 | for (code = 0; code < LENGTH_CODES-1; code++) { | 261 | for (code = 0; code < LENGTH_CODES-1; code++) { |
262 | base_length[code] = length; | 262 | base_length[code] = length; |
263 | for (n = 0; n < (1<<extra_lbits[code]); n++) { | 263 | for (n = 0; n < (1<<extra_lbits[code]); n++) { |
264 | _length_code[length++] = (uch)code; | 264 | _length_code[length++] = (uch)code; |
265 | } | 265 | } |
266 | } | 266 | } |
267 | Assert (length == 256, "tr_static_init: length != 256"); | 267 | Assert (length == 256, "tr_static_init: length != 256"); |
268 | /* Note that the length 255 (match length 258) can be represented | 268 | /* Note that the length 255 (match length 258) can be represented |
269 | * in two different ways: code 284 + 5 bits or code 285, so we | 269 | * in two different ways: code 284 + 5 bits or code 285, so we |
270 | * overwrite length_code[255] to use the best encoding: | 270 | * overwrite length_code[255] to use the best encoding: |
271 | */ | 271 | */ |
272 | _length_code[length-1] = (uch)code; | 272 | _length_code[length-1] = (uch)code; |
273 | 273 | ||
274 | /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ | 274 | /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ |
275 | dist = 0; | 275 | dist = 0; |
276 | for (code = 0 ; code < 16; code++) { | 276 | for (code = 0 ; code < 16; code++) { |
277 | base_dist[code] = dist; | 277 | base_dist[code] = dist; |
278 | for (n = 0; n < (1<<extra_dbits[code]); n++) { | 278 | for (n = 0; n < (1<<extra_dbits[code]); n++) { |
279 | _dist_code[dist++] = (uch)code; | 279 | _dist_code[dist++] = (uch)code; |
280 | } | 280 | } |
281 | } | 281 | } |
282 | Assert (dist == 256, "tr_static_init: dist != 256"); | 282 | Assert (dist == 256, "tr_static_init: dist != 256"); |
283 | dist >>= 7; /* from now on, all distances are divided by 128 */ | 283 | dist >>= 7; /* from now on, all distances are divided by 128 */ |
284 | for ( ; code < D_CODES; code++) { | 284 | for ( ; code < D_CODES; code++) { |
285 | base_dist[code] = dist << 7; | 285 | base_dist[code] = dist << 7; |
286 | for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { | 286 | for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { |
287 | _dist_code[256 + dist++] = (uch)code; | 287 | _dist_code[256 + dist++] = (uch)code; |
288 | } | 288 | } |
289 | } | 289 | } |
290 | Assert (dist == 256, "tr_static_init: 256+dist != 512"); | 290 | Assert (dist == 256, "tr_static_init: 256+dist != 512"); |
291 | 291 | ||
292 | /* Construct the codes of the static literal tree */ | 292 | /* Construct the codes of the static literal tree */ |
293 | for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; | 293 | for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; |
294 | n = 0; | 294 | n = 0; |
295 | while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; | 295 | while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; |
296 | while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; | 296 | while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; |
297 | while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; | 297 | while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; |
298 | while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; | 298 | while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; |
299 | /* Codes 286 and 287 do not exist, but we must include them in the | 299 | /* Codes 286 and 287 do not exist, but we must include them in the |
300 | * tree construction to get a canonical Huffman tree (longest code | 300 | * tree construction to get a canonical Huffman tree (longest code |
301 | * all ones) | 301 | * all ones) |
302 | */ | 302 | */ |
303 | gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); | 303 | gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); |
304 | 304 | ||
305 | /* The static distance tree is trivial: */ | 305 | /* The static distance tree is trivial: */ |
306 | for (n = 0; n < D_CODES; n++) { | 306 | for (n = 0; n < D_CODES; n++) { |
307 | static_dtree[n].Len = 5; | 307 | static_dtree[n].Len = 5; |
308 | static_dtree[n].Code = bi_reverse((unsigned)n, 5); | 308 | static_dtree[n].Code = bi_reverse((unsigned)n, 5); |
309 | } | 309 | } |
310 | static_init_done = 1; | 310 | static_init_done = 1; |
311 | 311 | ||
312 | # ifdef GEN_TREES_H | 312 | # ifdef GEN_TREES_H |
313 | gen_trees_header(); | 313 | gen_trees_header(); |
314 | # endif | 314 | # endif |
315 | #endif /* defined(GEN_TREES_H) || !defined(STDC) */ | 315 | #endif /* defined(GEN_TREES_H) || !defined(STDC) */ |
316 | } | 316 | } |
317 | 317 | ||
318 | /* =========================================================================== | 318 | /* =========================================================================== |
319 | * Genererate the file trees.h describing the static trees. | 319 | * Genererate the file trees.h describing the static trees. |
320 | */ | 320 | */ |
321 | #ifdef GEN_TREES_H | 321 | #ifdef GEN_TREES_H |
322 | # ifndef DEBUG | 322 | # ifndef DEBUG |
323 | # include <stdio.h> | 323 | # include <stdio.h> |
324 | # endif | 324 | # endif |
325 | 325 | ||
326 | # define SEPARATOR(i, last, width) \ | 326 | # define SEPARATOR(i, last, width) \ |
327 | ((i) == (last)? "\n};\n\n" : \ | 327 | ((i) == (last)? "\n};\n\n" : \ |
328 | ((i) % (width) == (width)-1 ? ",\n" : ", ")) | 328 | ((i) % (width) == (width)-1 ? ",\n" : ", ")) |
329 | 329 | ||
330 | void gen_trees_header() | 330 | void gen_trees_header() |
331 | { | 331 | { |
332 | FILE *header = fopen("trees.h", "w"); | 332 | FILE *header = fopen("trees.h", "w"); |
333 | int i; | 333 | int i; |
334 | 334 | ||
335 | Assert (header != NULL, "Can't open trees.h"); | 335 | Assert (header != NULL, "Can't open trees.h"); |
336 | fprintf(header, | 336 | fprintf(header, |
337 | "/* header created automatically with -DGEN_TREES_H */\n\n"); | 337 | "/* header created automatically with -DGEN_TREES_H */\n\n"); |
338 | 338 | ||
339 | fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n"); | 339 | fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n"); |
340 | for (i = 0; i < L_CODES+2; i++) { | 340 | for (i = 0; i < L_CODES+2; i++) { |
341 | fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code, | 341 | fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code, |
342 | static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5)); | 342 | static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5)); |
343 | } | 343 | } |
344 | 344 | ||
345 | fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n"); | 345 | fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n"); |
346 | for (i = 0; i < D_CODES; i++) { | 346 | for (i = 0; i < D_CODES; i++) { |
347 | fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code, | 347 | fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code, |
348 | static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5)); | 348 | static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5)); |
349 | } | 349 | } |
350 | 350 | ||
351 | fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n"); | 351 | fprintf(header, "const uch _dist_code[DIST_CODE_LEN] = {\n"); |
352 | for (i = 0; i < DIST_CODE_LEN; i++) { | 352 | for (i = 0; i < DIST_CODE_LEN; i++) { |
353 | fprintf(header, "%2u%s", _dist_code[i], | 353 | fprintf(header, "%2u%s", _dist_code[i], |
354 | SEPARATOR(i, DIST_CODE_LEN-1, 20)); | 354 | SEPARATOR(i, DIST_CODE_LEN-1, 20)); |
355 | } | 355 | } |
356 | 356 | ||
357 | fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n"); | 357 | fprintf(header, "const uch _length_code[MAX_MATCH-MIN_MATCH+1]= {\n"); |
358 | for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) { | 358 | for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) { |
359 | fprintf(header, "%2u%s", _length_code[i], | 359 | fprintf(header, "%2u%s", _length_code[i], |
360 | SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20)); | 360 | SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20)); |
361 | } | 361 | } |
362 | 362 | ||
363 | fprintf(header, "local const int base_length[LENGTH_CODES] = {\n"); | 363 | fprintf(header, "local const int base_length[LENGTH_CODES] = {\n"); |
364 | for (i = 0; i < LENGTH_CODES; i++) { | 364 | for (i = 0; i < LENGTH_CODES; i++) { |
365 | fprintf(header, "%1u%s", base_length[i], | 365 | fprintf(header, "%1u%s", base_length[i], |
366 | SEPARATOR(i, LENGTH_CODES-1, 20)); | 366 | SEPARATOR(i, LENGTH_CODES-1, 20)); |
367 | } | 367 | } |
368 | 368 | ||
369 | fprintf(header, "local const int base_dist[D_CODES] = {\n"); | 369 | fprintf(header, "local const int base_dist[D_CODES] = {\n"); |
370 | for (i = 0; i < D_CODES; i++) { | 370 | for (i = 0; i < D_CODES; i++) { |
371 | fprintf(header, "%5u%s", base_dist[i], | 371 | fprintf(header, "%5u%s", base_dist[i], |
372 | SEPARATOR(i, D_CODES-1, 10)); | 372 | SEPARATOR(i, D_CODES-1, 10)); |
373 | } | 373 | } |
374 | 374 | ||
375 | fclose(header); | 375 | fclose(header); |
376 | } | 376 | } |
377 | #endif /* GEN_TREES_H */ | 377 | #endif /* GEN_TREES_H */ |
378 | 378 | ||
379 | /* =========================================================================== | 379 | /* =========================================================================== |
380 | * Initialize the tree data structures for a new zlib stream. | 380 | * Initialize the tree data structures for a new zlib stream. |
381 | */ | 381 | */ |
382 | void _tr_init(s) | 382 | void _tr_init(s) |
383 | deflate_state *s; | 383 | deflate_state *s; |
384 | { | 384 | { |
385 | tr_static_init(); | 385 | tr_static_init(); |
386 | 386 | ||
387 | s->l_desc.dyn_tree = s->dyn_ltree; | 387 | s->l_desc.dyn_tree = s->dyn_ltree; |
388 | s->l_desc.stat_desc = &static_l_desc; | 388 | s->l_desc.stat_desc = &static_l_desc; |
389 | 389 | ||
390 | s->d_desc.dyn_tree = s->dyn_dtree; | 390 | s->d_desc.dyn_tree = s->dyn_dtree; |
391 | s->d_desc.stat_desc = &static_d_desc; | 391 | s->d_desc.stat_desc = &static_d_desc; |
392 | 392 | ||
393 | s->bl_desc.dyn_tree = s->bl_tree; | 393 | s->bl_desc.dyn_tree = s->bl_tree; |
394 | s->bl_desc.stat_desc = &static_bl_desc; | 394 | s->bl_desc.stat_desc = &static_bl_desc; |
395 | 395 | ||
396 | s->bi_buf = 0; | 396 | s->bi_buf = 0; |
397 | s->bi_valid = 0; | 397 | s->bi_valid = 0; |
398 | s->last_eob_len = 8; /* enough lookahead for inflate */ | 398 | s->last_eob_len = 8; /* enough lookahead for inflate */ |
399 | #ifdef DEBUG | 399 | #ifdef DEBUG |
400 | s->compressed_len = 0L; | 400 | s->compressed_len = 0L; |
401 | s->bits_sent = 0L; | 401 | s->bits_sent = 0L; |
402 | #endif | 402 | #endif |
403 | 403 | ||
404 | /* Initialize the first block of the first file: */ | 404 | /* Initialize the first block of the first file: */ |
405 | init_block(s); | 405 | init_block(s); |
406 | } | 406 | } |
407 | 407 | ||
408 | /* =========================================================================== | 408 | /* =========================================================================== |
409 | * Initialize a new block. | 409 | * Initialize a new block. |
410 | */ | 410 | */ |
411 | local void init_block(s) | 411 | local void init_block(s) |
412 | deflate_state *s; | 412 | deflate_state *s; |
413 | { | 413 | { |
414 | int n; /* iterates over tree elements */ | 414 | int n; /* iterates over tree elements */ |
415 | 415 | ||
416 | /* Initialize the trees. */ | 416 | /* Initialize the trees. */ |
417 | for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; | 417 | for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; |
418 | for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; | 418 | for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; |
419 | for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; | 419 | for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; |
420 | 420 | ||
421 | s->dyn_ltree[END_BLOCK].Freq = 1; | 421 | s->dyn_ltree[END_BLOCK].Freq = 1; |
422 | s->opt_len = s->static_len = 0L; | 422 | s->opt_len = s->static_len = 0L; |
423 | s->last_lit = s->matches = 0; | 423 | s->last_lit = s->matches = 0; |
424 | } | 424 | } |
425 | 425 | ||
426 | #define SMALLEST 1 | 426 | #define SMALLEST 1 |
427 | /* Index within the heap array of least frequent node in the Huffman tree */ | 427 | /* Index within the heap array of least frequent node in the Huffman tree */ |
428 | 428 | ||
429 | 429 | ||
430 | /* =========================================================================== | 430 | /* =========================================================================== |
431 | * Remove the smallest element from the heap and recreate the heap with | 431 | * Remove the smallest element from the heap and recreate the heap with |
432 | * one less element. Updates heap and heap_len. | 432 | * one less element. Updates heap and heap_len. |
433 | */ | 433 | */ |
434 | #define pqremove(s, tree, top) \ | 434 | #define pqremove(s, tree, top) \ |
435 | {\ | 435 | {\ |
436 | top = s->heap[SMALLEST]; \ | 436 | top = s->heap[SMALLEST]; \ |
437 | s->heap[SMALLEST] = s->heap[s->heap_len--]; \ | 437 | s->heap[SMALLEST] = s->heap[s->heap_len--]; \ |
438 | pqdownheap(s, tree, SMALLEST); \ | 438 | pqdownheap(s, tree, SMALLEST); \ |
439 | } | 439 | } |
440 | 440 | ||
441 | /* =========================================================================== | 441 | /* =========================================================================== |
442 | * Compares to subtrees, using the tree depth as tie breaker when | 442 | * Compares to subtrees, using the tree depth as tie breaker when |
443 | * the subtrees have equal frequency. This minimizes the worst case length. | 443 | * the subtrees have equal frequency. This minimizes the worst case length. |
444 | */ | 444 | */ |
445 | #define smaller(tree, n, m, depth) \ | 445 | #define smaller(tree, n, m, depth) \ |
446 | (tree[n].Freq < tree[m].Freq || \ | 446 | (tree[n].Freq < tree[m].Freq || \ |
447 | (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) | 447 | (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) |
448 | 448 | ||
449 | /* =========================================================================== | 449 | /* =========================================================================== |
450 | * Restore the heap property by moving down the tree starting at node k, | 450 | * Restore the heap property by moving down the tree starting at node k, |
451 | * exchanging a node with the smallest of its two sons if necessary, stopping | 451 | * exchanging a node with the smallest of its two sons if necessary, stopping |
452 | * when the heap property is re-established (each father smaller than its | 452 | * when the heap property is re-established (each father smaller than its |
453 | * two sons). | 453 | * two sons). |
454 | */ | 454 | */ |
455 | local void pqdownheap(s, tree, k) | 455 | local void pqdownheap(s, tree, k) |
456 | deflate_state *s; | 456 | deflate_state *s; |
457 | ct_data *tree; /* the tree to restore */ | 457 | ct_data *tree; /* the tree to restore */ |
458 | int k; /* node to move down */ | 458 | int k; /* node to move down */ |
459 | { | 459 | { |
460 | int v = s->heap[k]; | 460 | int v = s->heap[k]; |
461 | int j = k << 1; /* left son of k */ | 461 | int j = k << 1; /* left son of k */ |
462 | while (j <= s->heap_len) { | 462 | while (j <= s->heap_len) { |
463 | /* Set j to the smallest of the two sons: */ | 463 | /* Set j to the smallest of the two sons: */ |
464 | if (j < s->heap_len && | 464 | if (j < s->heap_len && |
465 | smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { | 465 | smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { |
466 | j++; | 466 | j++; |
467 | } | 467 | } |
468 | /* Exit if v is smaller than both sons */ | 468 | /* Exit if v is smaller than both sons */ |
469 | if (smaller(tree, v, s->heap[j], s->depth)) break; | 469 | if (smaller(tree, v, s->heap[j], s->depth)) break; |
470 | 470 | ||
471 | /* Exchange v with the smallest son */ | 471 | /* Exchange v with the smallest son */ |
472 | s->heap[k] = s->heap[j]; k = j; | 472 | s->heap[k] = s->heap[j]; k = j; |
473 | 473 | ||
474 | /* And continue down the tree, setting j to the left son of k */ | 474 | /* And continue down the tree, setting j to the left son of k */ |
475 | j <<= 1; | 475 | j <<= 1; |
476 | } | 476 | } |
477 | s->heap[k] = v; | 477 | s->heap[k] = v; |
478 | } | 478 | } |
479 | 479 | ||
480 | /* =========================================================================== | 480 | /* =========================================================================== |
481 | * Compute the optimal bit lengths for a tree and update the total bit length | 481 | * Compute the optimal bit lengths for a tree and update the total bit length |
482 | * for the current block. | 482 | * for the current block. |
483 | * IN assertion: the fields freq and dad are set, heap[heap_max] and | 483 | * IN assertion: the fields freq and dad are set, heap[heap_max] and |
484 | * above are the tree nodes sorted by increasing frequency. | 484 | * above are the tree nodes sorted by increasing frequency. |
485 | * OUT assertions: the field len is set to the optimal bit length, the | 485 | * OUT assertions: the field len is set to the optimal bit length, the |
486 | * array bl_count contains the frequencies for each bit length. | 486 | * array bl_count contains the frequencies for each bit length. |
487 | * The length opt_len is updated; static_len is also updated if stree is | 487 | * The length opt_len is updated; static_len is also updated if stree is |
488 | * not null. | 488 | * not null. |
489 | */ | 489 | */ |
490 | local void gen_bitlen(s, desc) | 490 | local void gen_bitlen(s, desc) |
491 | deflate_state *s; | 491 | deflate_state *s; |
492 | tree_desc *desc; /* the tree descriptor */ | 492 | tree_desc *desc; /* the tree descriptor */ |
493 | { | 493 | { |
494 | ct_data *tree = desc->dyn_tree; | 494 | ct_data *tree = desc->dyn_tree; |
495 | int max_code = desc->max_code; | 495 | int max_code = desc->max_code; |
496 | const ct_data *stree = desc->stat_desc->static_tree; | 496 | const ct_data *stree = desc->stat_desc->static_tree; |
497 | const intf *extra = desc->stat_desc->extra_bits; | 497 | const intf *extra = desc->stat_desc->extra_bits; |
498 | int base = desc->stat_desc->extra_base; | 498 | int base = desc->stat_desc->extra_base; |
499 | int max_length = desc->stat_desc->max_length; | 499 | int max_length = desc->stat_desc->max_length; |
500 | int h; /* heap index */ | 500 | int h; /* heap index */ |
501 | int n, m; /* iterate over the tree elements */ | 501 | int n, m; /* iterate over the tree elements */ |
502 | int bits; /* bit length */ | 502 | int bits; /* bit length */ |
503 | int xbits; /* extra bits */ | 503 | int xbits; /* extra bits */ |
504 | ush f; /* frequency */ | 504 | ush f; /* frequency */ |
505 | int overflow = 0; /* number of elements with bit length too large */ | 505 | int overflow = 0; /* number of elements with bit length too large */ |
506 | 506 | ||
507 | for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; | 507 | for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; |
508 | 508 | ||
509 | /* In a first pass, compute the optimal bit lengths (which may | 509 | /* In a first pass, compute the optimal bit lengths (which may |
510 | * overflow in the case of the bit length tree). | 510 | * overflow in the case of the bit length tree). |
511 | */ | 511 | */ |
512 | tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ | 512 | tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ |
513 | 513 | ||
514 | for (h = s->heap_max+1; h < HEAP_SIZE; h++) { | 514 | for (h = s->heap_max+1; h < HEAP_SIZE; h++) { |
515 | n = s->heap[h]; | 515 | n = s->heap[h]; |
516 | bits = tree[tree[n].Dad].Len + 1; | 516 | bits = tree[tree[n].Dad].Len + 1; |
517 | if (bits > max_length) bits = max_length, overflow++; | 517 | if (bits > max_length) bits = max_length, overflow++; |
518 | tree[n].Len = (ush)bits; | 518 | tree[n].Len = (ush)bits; |
519 | /* We overwrite tree[n].Dad which is no longer needed */ | 519 | /* We overwrite tree[n].Dad which is no longer needed */ |
520 | 520 | ||
521 | if (n > max_code) continue; /* not a leaf node */ | 521 | if (n > max_code) continue; /* not a leaf node */ |
522 | 522 | ||
523 | s->bl_count[bits]++; | 523 | s->bl_count[bits]++; |
524 | xbits = 0; | 524 | xbits = 0; |
525 | if (n >= base) xbits = extra[n-base]; | 525 | if (n >= base) xbits = extra[n-base]; |
526 | f = tree[n].Freq; | 526 | f = tree[n].Freq; |
527 | s->opt_len += (ulg)f * (bits + xbits); | 527 | s->opt_len += (ulg)f * (bits + xbits); |
528 | if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); | 528 | if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); |
529 | } | 529 | } |
530 | if (overflow == 0) return; | 530 | if (overflow == 0) return; |
531 | 531 | ||
532 | Trace((stderr,"\nbit length overflow\n")); | 532 | Trace((stderr,"\nbit length overflow\n")); |
533 | /* This happens for example on obj2 and pic of the Calgary corpus */ | 533 | /* This happens for example on obj2 and pic of the Calgary corpus */ |
534 | 534 | ||
535 | /* Find the first bit length which could increase: */ | 535 | /* Find the first bit length which could increase: */ |
536 | do { | 536 | do { |
537 | bits = max_length-1; | 537 | bits = max_length-1; |
538 | while (s->bl_count[bits] == 0) bits--; | 538 | while (s->bl_count[bits] == 0) bits--; |
539 | s->bl_count[bits]--; /* move one leaf down the tree */ | 539 | s->bl_count[bits]--; /* move one leaf down the tree */ |
540 | s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ | 540 | s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ |
541 | s->bl_count[max_length]--; | 541 | s->bl_count[max_length]--; |
542 | /* The brother of the overflow item also moves one step up, | 542 | /* The brother of the overflow item also moves one step up, |
543 | * but this does not affect bl_count[max_length] | 543 | * but this does not affect bl_count[max_length] |
544 | */ | 544 | */ |
545 | overflow -= 2; | 545 | overflow -= 2; |
546 | } while (overflow > 0); | 546 | } while (overflow > 0); |
547 | 547 | ||
548 | /* Now recompute all bit lengths, scanning in increasing frequency. | 548 | /* Now recompute all bit lengths, scanning in increasing frequency. |
549 | * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all | 549 | * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all |
550 | * lengths instead of fixing only the wrong ones. This idea is taken | 550 | * lengths instead of fixing only the wrong ones. This idea is taken |
551 | * from 'ar' written by Haruhiko Okumura.) | 551 | * from 'ar' written by Haruhiko Okumura.) |
552 | */ | 552 | */ |
553 | for (bits = max_length; bits != 0; bits--) { | 553 | for (bits = max_length; bits != 0; bits--) { |
554 | n = s->bl_count[bits]; | 554 | n = s->bl_count[bits]; |
555 | while (n != 0) { | 555 | while (n != 0) { |
556 | m = s->heap[--h]; | 556 | m = s->heap[--h]; |
557 | if (m > max_code) continue; | 557 | if (m > max_code) continue; |
558 | if ((unsigned) tree[m].Len != (unsigned) bits) { | 558 | if ((unsigned) tree[m].Len != (unsigned) bits) { |
559 | Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); | 559 | Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); |
560 | s->opt_len += ((long)bits - (long)tree[m].Len) | 560 | s->opt_len += ((long)bits - (long)tree[m].Len) |
561 | *(long)tree[m].Freq; | 561 | *(long)tree[m].Freq; |
562 | tree[m].Len = (ush)bits; | 562 | tree[m].Len = (ush)bits; |
563 | } | 563 | } |
564 | n--; | 564 | n--; |
565 | } | 565 | } |
566 | } | 566 | } |
567 | } | 567 | } |
568 | 568 | ||
569 | /* =========================================================================== | 569 | /* =========================================================================== |
570 | * Generate the codes for a given tree and bit counts (which need not be | 570 | * Generate the codes for a given tree and bit counts (which need not be |
571 | * optimal). | 571 | * optimal). |
572 | * IN assertion: the array bl_count contains the bit length statistics for | 572 | * IN assertion: the array bl_count contains the bit length statistics for |
573 | * the given tree and the field len is set for all tree elements. | 573 | * the given tree and the field len is set for all tree elements. |
574 | * OUT assertion: the field code is set for all tree elements of non | 574 | * OUT assertion: the field code is set for all tree elements of non |
575 | * zero code length. | 575 | * zero code length. |
576 | */ | 576 | */ |
577 | local void gen_codes (tree, max_code, bl_count) | 577 | local void gen_codes (tree, max_code, bl_count) |
578 | ct_data *tree; /* the tree to decorate */ | 578 | ct_data *tree; /* the tree to decorate */ |
579 | int max_code; /* largest code with non zero frequency */ | 579 | int max_code; /* largest code with non zero frequency */ |
580 | ushf *bl_count; /* number of codes at each bit length */ | 580 | ushf *bl_count; /* number of codes at each bit length */ |
581 | { | 581 | { |
582 | ush next_code[MAX_BITS+1]; /* next code value for each bit length */ | 582 | ush next_code[MAX_BITS+1]; /* next code value for each bit length */ |
583 | ush code = 0; /* running code value */ | 583 | ush code = 0; /* running code value */ |
584 | int bits; /* bit index */ | 584 | int bits; /* bit index */ |
585 | int n; /* code index */ | 585 | int n; /* code index */ |
586 | 586 | ||
587 | /* The distribution counts are first used to generate the code values | 587 | /* The distribution counts are first used to generate the code values |
588 | * without bit reversal. | 588 | * without bit reversal. |
589 | */ | 589 | */ |
590 | for (bits = 1; bits <= MAX_BITS; bits++) { | 590 | for (bits = 1; bits <= MAX_BITS; bits++) { |
591 | next_code[bits] = code = (code + bl_count[bits-1]) << 1; | 591 | next_code[bits] = code = (code + bl_count[bits-1]) << 1; |
592 | } | 592 | } |
593 | /* Check that the bit counts in bl_count are consistent. The last code | 593 | /* Check that the bit counts in bl_count are consistent. The last code |
594 | * must be all ones. | 594 | * must be all ones. |
595 | */ | 595 | */ |
596 | Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, | 596 | Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, |
597 | "inconsistent bit counts"); | 597 | "inconsistent bit counts"); |
598 | Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); | 598 | Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); |
599 | 599 | ||
600 | for (n = 0; n <= max_code; n++) { | 600 | for (n = 0; n <= max_code; n++) { |
601 | int len = tree[n].Len; | 601 | int len = tree[n].Len; |
602 | if (len == 0) continue; | 602 | if (len == 0) continue; |
603 | /* Now reverse the bits */ | 603 | /* Now reverse the bits */ |
604 | tree[n].Code = bi_reverse(next_code[len]++, len); | 604 | tree[n].Code = bi_reverse(next_code[len]++, len); |
605 | 605 | ||
606 | Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", | 606 | Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", |
607 | n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); | 607 | n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); |
608 | } | 608 | } |
609 | } | 609 | } |
610 | 610 | ||
611 | /* =========================================================================== | 611 | /* =========================================================================== |
612 | * Construct one Huffman tree and assigns the code bit strings and lengths. | 612 | * Construct one Huffman tree and assigns the code bit strings and lengths. |
613 | * Update the total bit length for the current block. | 613 | * Update the total bit length for the current block. |
614 | * IN assertion: the field freq is set for all tree elements. | 614 | * IN assertion: the field freq is set for all tree elements. |
615 | * OUT assertions: the fields len and code are set to the optimal bit length | 615 | * OUT assertions: the fields len and code are set to the optimal bit length |
616 | * and corresponding code. The length opt_len is updated; static_len is | 616 | * and corresponding code. The length opt_len is updated; static_len is |
617 | * also updated if stree is not null. The field max_code is set. | 617 | * also updated if stree is not null. The field max_code is set. |
618 | */ | 618 | */ |
619 | local void build_tree(s, desc) | 619 | local void build_tree(s, desc) |
620 | deflate_state *s; | 620 | deflate_state *s; |
621 | tree_desc *desc; /* the tree descriptor */ | 621 | tree_desc *desc; /* the tree descriptor */ |
622 | { | 622 | { |
623 | ct_data *tree = desc->dyn_tree; | 623 | ct_data *tree = desc->dyn_tree; |
624 | const ct_data *stree = desc->stat_desc->static_tree; | 624 | const ct_data *stree = desc->stat_desc->static_tree; |
625 | int elems = desc->stat_desc->elems; | 625 | int elems = desc->stat_desc->elems; |
626 | int n, m; /* iterate over heap elements */ | 626 | int n, m; /* iterate over heap elements */ |
627 | int max_code = -1; /* largest code with non zero frequency */ | 627 | int max_code = -1; /* largest code with non zero frequency */ |
628 | int node; /* new node being created */ | 628 | int node; /* new node being created */ |
629 | 629 | ||
630 | /* Construct the initial heap, with least frequent element in | 630 | /* Construct the initial heap, with least frequent element in |
631 | * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. | 631 | * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. |
632 | * heap[0] is not used. | 632 | * heap[0] is not used. |
633 | */ | 633 | */ |
634 | s->heap_len = 0, s->heap_max = HEAP_SIZE; | 634 | s->heap_len = 0, s->heap_max = HEAP_SIZE; |
635 | 635 | ||
636 | for (n = 0; n < elems; n++) { | 636 | for (n = 0; n < elems; n++) { |
637 | if (tree[n].Freq != 0) { | 637 | if (tree[n].Freq != 0) { |
638 | s->heap[++(s->heap_len)] = max_code = n; | 638 | s->heap[++(s->heap_len)] = max_code = n; |
639 | s->depth[n] = 0; | 639 | s->depth[n] = 0; |
640 | } else { | 640 | } else { |
641 | tree[n].Len = 0; | 641 | tree[n].Len = 0; |
642 | } | 642 | } |
643 | } | 643 | } |
644 | 644 | ||
645 | /* The pkzip format requires that at least one distance code exists, | 645 | /* The pkzip format requires that at least one distance code exists, |
646 | * and that at least one bit should be sent even if there is only one | 646 | * and that at least one bit should be sent even if there is only one |
647 | * possible code. So to avoid special checks later on we force at least | 647 | * possible code. So to avoid special checks later on we force at least |
648 | * two codes of non zero frequency. | 648 | * two codes of non zero frequency. |
649 | */ | 649 | */ |
650 | while (s->heap_len < 2) { | 650 | while (s->heap_len < 2) { |
651 | node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); | 651 | node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); |
652 | tree[node].Freq = 1; | 652 | tree[node].Freq = 1; |
653 | s->depth[node] = 0; | 653 | s->depth[node] = 0; |
654 | s->opt_len--; if (stree) s->static_len -= stree[node].Len; | 654 | s->opt_len--; if (stree) s->static_len -= stree[node].Len; |
655 | /* node is 0 or 1 so it does not have extra bits */ | 655 | /* node is 0 or 1 so it does not have extra bits */ |
656 | } | 656 | } |
657 | desc->max_code = max_code; | 657 | desc->max_code = max_code; |
658 | 658 | ||
659 | /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, | 659 | /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, |
660 | * establish sub-heaps of increasing lengths: | 660 | * establish sub-heaps of increasing lengths: |
661 | */ | 661 | */ |
662 | for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); | 662 | for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); |
663 | 663 | ||
664 | /* Construct the Huffman tree by repeatedly combining the least two | 664 | /* Construct the Huffman tree by repeatedly combining the least two |
665 | * frequent nodes. | 665 | * frequent nodes. |
666 | */ | 666 | */ |
667 | node = elems; /* next internal node of the tree */ | 667 | node = elems; /* next internal node of the tree */ |
668 | do { | 668 | do { |
669 | pqremove(s, tree, n); /* n = node of least frequency */ | 669 | pqremove(s, tree, n); /* n = node of least frequency */ |
670 | m = s->heap[SMALLEST]; /* m = node of next least frequency */ | 670 | m = s->heap[SMALLEST]; /* m = node of next least frequency */ |
671 | 671 | ||
672 | s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ | 672 | s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ |
673 | s->heap[--(s->heap_max)] = m; | 673 | s->heap[--(s->heap_max)] = m; |
674 | 674 | ||
675 | /* Create a new node father of n and m */ | 675 | /* Create a new node father of n and m */ |
676 | tree[node].Freq = tree[n].Freq + tree[m].Freq; | 676 | tree[node].Freq = tree[n].Freq + tree[m].Freq; |
677 | s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ? | 677 | s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ? |
678 | s->depth[n] : s->depth[m]) + 1); | 678 | s->depth[n] : s->depth[m]) + 1); |
679 | tree[n].Dad = tree[m].Dad = (ush)node; | 679 | tree[n].Dad = tree[m].Dad = (ush)node; |
680 | #ifdef DUMP_BL_TREE | 680 | #ifdef DUMP_BL_TREE |
681 | if (tree == s->bl_tree) { | 681 | if (tree == s->bl_tree) { |
682 | fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", | 682 | fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", |
683 | node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); | 683 | node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); |
684 | } | 684 | } |
685 | #endif | 685 | #endif |
686 | /* and insert the new node in the heap */ | 686 | /* and insert the new node in the heap */ |
687 | s->heap[SMALLEST] = node++; | 687 | s->heap[SMALLEST] = node++; |
688 | pqdownheap(s, tree, SMALLEST); | 688 | pqdownheap(s, tree, SMALLEST); |
689 | 689 | ||
690 | } while (s->heap_len >= 2); | 690 | } while (s->heap_len >= 2); |
691 | 691 | ||
692 | s->heap[--(s->heap_max)] = s->heap[SMALLEST]; | 692 | s->heap[--(s->heap_max)] = s->heap[SMALLEST]; |
693 | 693 | ||
694 | /* At this point, the fields freq and dad are set. We can now | 694 | /* At this point, the fields freq and dad are set. We can now |
695 | * generate the bit lengths. | 695 | * generate the bit lengths. |
696 | */ | 696 | */ |
697 | gen_bitlen(s, (tree_desc *)desc); | 697 | gen_bitlen(s, (tree_desc *)desc); |
698 | 698 | ||
699 | /* The field len is now set, we can generate the bit codes */ | 699 | /* The field len is now set, we can generate the bit codes */ |
700 | gen_codes ((ct_data *)tree, max_code, s->bl_count); | 700 | gen_codes ((ct_data *)tree, max_code, s->bl_count); |
701 | } | 701 | } |
702 | 702 | ||
703 | /* =========================================================================== | 703 | /* =========================================================================== |
704 | * Scan a literal or distance tree to determine the frequencies of the codes | 704 | * Scan a literal or distance tree to determine the frequencies of the codes |
705 | * in the bit length tree. | 705 | * in the bit length tree. |
706 | */ | 706 | */ |
707 | local void scan_tree (s, tree, max_code) | 707 | local void scan_tree (s, tree, max_code) |
708 | deflate_state *s; | 708 | deflate_state *s; |
709 | ct_data *tree; /* the tree to be scanned */ | 709 | ct_data *tree; /* the tree to be scanned */ |
710 | int max_code; /* and its largest code of non zero frequency */ | 710 | int max_code; /* and its largest code of non zero frequency */ |
711 | { | 711 | { |
712 | int n; /* iterates over all tree elements */ | 712 | int n; /* iterates over all tree elements */ |
713 | int prevlen = -1; /* last emitted length */ | 713 | int prevlen = -1; /* last emitted length */ |
714 | int curlen; /* length of current code */ | 714 | int curlen; /* length of current code */ |
715 | int nextlen = tree[0].Len; /* length of next code */ | 715 | int nextlen = tree[0].Len; /* length of next code */ |
716 | int count = 0; /* repeat count of the current code */ | 716 | int count = 0; /* repeat count of the current code */ |
717 | int max_count = 7; /* max repeat count */ | 717 | int max_count = 7; /* max repeat count */ |
718 | int min_count = 4; /* min repeat count */ | 718 | int min_count = 4; /* min repeat count */ |
719 | 719 | ||
720 | if (nextlen == 0) max_count = 138, min_count = 3; | 720 | if (nextlen == 0) max_count = 138, min_count = 3; |
721 | tree[max_code+1].Len = (ush)0xffff; /* guard */ | 721 | tree[max_code+1].Len = (ush)0xffff; /* guard */ |
722 | 722 | ||
723 | for (n = 0; n <= max_code; n++) { | 723 | for (n = 0; n <= max_code; n++) { |
724 | curlen = nextlen; nextlen = tree[n+1].Len; | 724 | curlen = nextlen; nextlen = tree[n+1].Len; |
725 | if (++count < max_count && curlen == nextlen) { | 725 | if (++count < max_count && curlen == nextlen) { |
726 | continue; | 726 | continue; |
727 | } else if (count < min_count) { | 727 | } else if (count < min_count) { |
728 | s->bl_tree[curlen].Freq += count; | 728 | s->bl_tree[curlen].Freq += count; |
729 | } else if (curlen != 0) { | 729 | } else if (curlen != 0) { |
730 | if (curlen != prevlen) s->bl_tree[curlen].Freq++; | 730 | if (curlen != prevlen) s->bl_tree[curlen].Freq++; |
731 | s->bl_tree[REP_3_6].Freq++; | 731 | s->bl_tree[REP_3_6].Freq++; |
732 | } else if (count <= 10) { | 732 | } else if (count <= 10) { |
733 | s->bl_tree[REPZ_3_10].Freq++; | 733 | s->bl_tree[REPZ_3_10].Freq++; |
734 | } else { | 734 | } else { |
735 | s->bl_tree[REPZ_11_138].Freq++; | 735 | s->bl_tree[REPZ_11_138].Freq++; |
736 | } | 736 | } |
737 | count = 0; prevlen = curlen; | 737 | count = 0; prevlen = curlen; |
738 | if (nextlen == 0) { | 738 | if (nextlen == 0) { |
739 | max_count = 138, min_count = 3; | 739 | max_count = 138, min_count = 3; |
740 | } else if (curlen == nextlen) { | 740 | } else if (curlen == nextlen) { |
741 | max_count = 6, min_count = 3; | 741 | max_count = 6, min_count = 3; |
742 | } else { | 742 | } else { |
743 | max_count = 7, min_count = 4; | 743 | max_count = 7, min_count = 4; |
744 | } | 744 | } |
745 | } | 745 | } |
746 | } | 746 | } |
747 | 747 | ||
748 | /* =========================================================================== | 748 | /* =========================================================================== |
749 | * Send a literal or distance tree in compressed form, using the codes in | 749 | * Send a literal or distance tree in compressed form, using the codes in |
750 | * bl_tree. | 750 | * bl_tree. |
751 | */ | 751 | */ |
752 | local void send_tree (s, tree, max_code) | 752 | local void send_tree (s, tree, max_code) |
753 | deflate_state *s; | 753 | deflate_state *s; |
754 | ct_data *tree; /* the tree to be scanned */ | 754 | ct_data *tree; /* the tree to be scanned */ |
755 | int max_code; /* and its largest code of non zero frequency */ | 755 | int max_code; /* and its largest code of non zero frequency */ |
756 | { | 756 | { |
757 | int n; /* iterates over all tree elements */ | 757 | int n; /* iterates over all tree elements */ |
758 | int prevlen = -1; /* last emitted length */ | 758 | int prevlen = -1; /* last emitted length */ |
759 | int curlen; /* length of current code */ | 759 | int curlen; /* length of current code */ |
760 | int nextlen = tree[0].Len; /* length of next code */ | 760 | int nextlen = tree[0].Len; /* length of next code */ |
761 | int count = 0; /* repeat count of the current code */ | 761 | int count = 0; /* repeat count of the current code */ |
762 | int max_count = 7; /* max repeat count */ | 762 | int max_count = 7; /* max repeat count */ |
763 | int min_count = 4; /* min repeat count */ | 763 | int min_count = 4; /* min repeat count */ |
764 | 764 | ||
765 | /* tree[max_code+1].Len = -1; */ /* guard already set */ | 765 | /* tree[max_code+1].Len = -1; */ /* guard already set */ |
766 | if (nextlen == 0) max_count = 138, min_count = 3; | 766 | if (nextlen == 0) max_count = 138, min_count = 3; |
767 | 767 | ||
768 | for (n = 0; n <= max_code; n++) { | 768 | for (n = 0; n <= max_code; n++) { |
769 | curlen = nextlen; nextlen = tree[n+1].Len; | 769 | curlen = nextlen; nextlen = tree[n+1].Len; |
770 | if (++count < max_count && curlen == nextlen) { | 770 | if (++count < max_count && curlen == nextlen) { |
771 | continue; | 771 | continue; |
772 | } else if (count < min_count) { | 772 | } else if (count < min_count) { |
773 | do { send_code(s, curlen, s->bl_tree); } while (--count != 0); | 773 | do { send_code(s, curlen, s->bl_tree); } while (--count != 0); |
774 | 774 | ||
775 | } else if (curlen != 0) { | 775 | } else if (curlen != 0) { |
776 | if (curlen != prevlen) { | 776 | if (curlen != prevlen) { |
777 | send_code(s, curlen, s->bl_tree); count--; | 777 | send_code(s, curlen, s->bl_tree); count--; |
778 | } | 778 | } |
779 | Assert(count >= 3 && count <= 6, " 3_6?"); | 779 | Assert(count >= 3 && count <= 6, " 3_6?"); |
780 | send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); | 780 | send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); |
781 | 781 | ||
782 | } else if (count <= 10) { | 782 | } else if (count <= 10) { |
783 | send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); | 783 | send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); |
784 | 784 | ||
785 | } else { | 785 | } else { |
786 | send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); | 786 | send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); |
787 | } | 787 | } |
788 | count = 0; prevlen = curlen; | 788 | count = 0; prevlen = curlen; |
789 | if (nextlen == 0) { | 789 | if (nextlen == 0) { |
790 | max_count = 138, min_count = 3; | 790 | max_count = 138, min_count = 3; |
791 | } else if (curlen == nextlen) { | 791 | } else if (curlen == nextlen) { |
792 | max_count = 6, min_count = 3; | 792 | max_count = 6, min_count = 3; |
793 | } else { | 793 | } else { |
794 | max_count = 7, min_count = 4; | 794 | max_count = 7, min_count = 4; |
795 | } | 795 | } |
796 | } | 796 | } |
797 | } | 797 | } |
798 | 798 | ||
799 | /* =========================================================================== | 799 | /* =========================================================================== |
800 | * Construct the Huffman tree for the bit lengths and return the index in | 800 | * Construct the Huffman tree for the bit lengths and return the index in |
801 | * bl_order of the last bit length code to send. | 801 | * bl_order of the last bit length code to send. |
802 | */ | 802 | */ |
803 | local int build_bl_tree(s) | 803 | local int build_bl_tree(s) |
804 | deflate_state *s; | 804 | deflate_state *s; |
805 | { | 805 | { |
806 | int max_blindex; /* index of last bit length code of non zero freq */ | 806 | int max_blindex; /* index of last bit length code of non zero freq */ |
807 | 807 | ||
808 | /* Determine the bit length frequencies for literal and distance trees */ | 808 | /* Determine the bit length frequencies for literal and distance trees */ |
809 | scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); | 809 | scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); |
810 | scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); | 810 | scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); |
811 | 811 | ||
812 | /* Build the bit length tree: */ | 812 | /* Build the bit length tree: */ |
813 | build_tree(s, (tree_desc *)(&(s->bl_desc))); | 813 | build_tree(s, (tree_desc *)(&(s->bl_desc))); |
814 | /* opt_len now includes the length of the tree representations, except | 814 | /* opt_len now includes the length of the tree representations, except |
815 | * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. | 815 | * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. |
816 | */ | 816 | */ |
817 | 817 | ||
818 | /* Determine the number of bit length codes to send. The pkzip format | 818 | /* Determine the number of bit length codes to send. The pkzip format |
819 | * requires that at least 4 bit length codes be sent. (appnote.txt says | 819 | * requires that at least 4 bit length codes be sent. (appnote.txt says |
820 | * 3 but the actual value used is 4.) | 820 | * 3 but the actual value used is 4.) |
821 | */ | 821 | */ |
822 | for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { | 822 | for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { |
823 | if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; | 823 | if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; |
824 | } | 824 | } |
825 | /* Update opt_len to include the bit length tree and counts */ | 825 | /* Update opt_len to include the bit length tree and counts */ |
826 | s->opt_len += 3*(max_blindex+1) + 5+5+4; | 826 | s->opt_len += 3*(max_blindex+1) + 5+5+4; |
827 | Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", | 827 | Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", |
828 | s->opt_len, s->static_len)); | 828 | s->opt_len, s->static_len)); |
829 | 829 | ||
830 | return max_blindex; | 830 | return max_blindex; |
831 | } | 831 | } |
832 | 832 | ||
833 | /* =========================================================================== | 833 | /* =========================================================================== |
834 | * Send the header for a block using dynamic Huffman trees: the counts, the | 834 | * Send the header for a block using dynamic Huffman trees: the counts, the |
835 | * lengths of the bit length codes, the literal tree and the distance tree. | 835 | * lengths of the bit length codes, the literal tree and the distance tree. |
836 | * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. | 836 | * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. |
837 | */ | 837 | */ |
838 | local void send_all_trees(s, lcodes, dcodes, blcodes) | 838 | local void send_all_trees(s, lcodes, dcodes, blcodes) |
839 | deflate_state *s; | 839 | deflate_state *s; |
840 | int lcodes, dcodes, blcodes; /* number of codes for each tree */ | 840 | int lcodes, dcodes, blcodes; /* number of codes for each tree */ |
841 | { | 841 | { |
842 | int rank; /* index in bl_order */ | 842 | int rank; /* index in bl_order */ |
843 | 843 | ||
844 | Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); | 844 | Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); |
845 | Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, | 845 | Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, |
846 | "too many codes"); | 846 | "too many codes"); |
847 | Tracev((stderr, "\nbl counts: ")); | 847 | Tracev((stderr, "\nbl counts: ")); |
848 | send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ | 848 | send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ |
849 | send_bits(s, dcodes-1, 5); | 849 | send_bits(s, dcodes-1, 5); |
850 | send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ | 850 | send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ |
851 | for (rank = 0; rank < blcodes; rank++) { | 851 | for (rank = 0; rank < blcodes; rank++) { |
852 | Tracev((stderr, "\nbl code %2d ", bl_order[rank])); | 852 | Tracev((stderr, "\nbl code %2d ", bl_order[rank])); |
853 | send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); | 853 | send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); |
854 | } | 854 | } |
855 | Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); | 855 | Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); |
856 | 856 | ||
857 | send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ | 857 | send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ |
858 | Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); | 858 | Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); |
859 | 859 | ||
860 | send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ | 860 | send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ |
861 | Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); | 861 | Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); |
862 | } | 862 | } |
863 | 863 | ||
864 | /* =========================================================================== | 864 | /* =========================================================================== |
865 | * Send a stored block | 865 | * Send a stored block |
866 | */ | 866 | */ |
867 | void _tr_stored_block(s, buf, stored_len, eof) | 867 | void _tr_stored_block(s, buf, stored_len, eof) |
868 | deflate_state *s; | 868 | deflate_state *s; |
869 | charf *buf; /* input block */ | 869 | charf *buf; /* input block */ |
870 | ulg stored_len; /* length of input block */ | 870 | ulg stored_len; /* length of input block */ |
871 | int eof; /* true if this is the last block for a file */ | 871 | int eof; /* true if this is the last block for a file */ |
872 | { | 872 | { |
873 | send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ | 873 | send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ |
874 | #ifdef DEBUG | 874 | #ifdef DEBUG |
875 | s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L; | 875 | s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L; |
876 | s->compressed_len += (stored_len + 4) << 3; | 876 | s->compressed_len += (stored_len + 4) << 3; |
877 | #endif | 877 | #endif |
878 | copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ | 878 | copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ |
879 | } | 879 | } |
880 | 880 | ||
881 | /* =========================================================================== | 881 | /* =========================================================================== |
882 | * Send one empty static block to give enough lookahead for inflate. | 882 | * Send one empty static block to give enough lookahead for inflate. |
883 | * This takes 10 bits, of which 7 may remain in the bit buffer. | 883 | * This takes 10 bits, of which 7 may remain in the bit buffer. |
884 | * The current inflate code requires 9 bits of lookahead. If the | 884 | * The current inflate code requires 9 bits of lookahead. If the |
885 | * last two codes for the previous block (real code plus EOB) were coded | 885 | * last two codes for the previous block (real code plus EOB) were coded |
886 | * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode | 886 | * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode |
887 | * the last real code. In this case we send two empty static blocks instead | 887 | * the last real code. In this case we send two empty static blocks instead |
888 | * of one. (There are no problems if the previous block is stored or fixed.) | 888 | * of one. (There are no problems if the previous block is stored or fixed.) |
889 | * To simplify the code, we assume the worst case of last real code encoded | 889 | * To simplify the code, we assume the worst case of last real code encoded |
890 | * on one bit only. | 890 | * on one bit only. |
891 | */ | 891 | */ |
892 | void _tr_align(s) | 892 | void _tr_align(s) |
893 | deflate_state *s; | 893 | deflate_state *s; |
894 | { | 894 | { |
895 | send_bits(s, STATIC_TREES<<1, 3); | 895 | send_bits(s, STATIC_TREES<<1, 3); |
896 | send_code(s, END_BLOCK, static_ltree); | 896 | send_code(s, END_BLOCK, static_ltree); |
897 | #ifdef DEBUG | 897 | #ifdef DEBUG |
898 | s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ | 898 | s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ |
899 | #endif | 899 | #endif |
900 | bi_flush(s); | 900 | bi_flush(s); |
901 | /* Of the 10 bits for the empty block, we have already sent | 901 | /* Of the 10 bits for the empty block, we have already sent |
902 | * (10 - bi_valid) bits. The lookahead for the last real code (before | 902 | * (10 - bi_valid) bits. The lookahead for the last real code (before |
903 | * the EOB of the previous block) was thus at least one plus the length | 903 | * the EOB of the previous block) was thus at least one plus the length |
904 | * of the EOB plus what we have just sent of the empty static block. | 904 | * of the EOB plus what we have just sent of the empty static block. |
905 | */ | 905 | */ |
906 | if (1 + s->last_eob_len + 10 - s->bi_valid < 9) { | 906 | if (1 + s->last_eob_len + 10 - s->bi_valid < 9) { |
907 | send_bits(s, STATIC_TREES<<1, 3); | 907 | send_bits(s, STATIC_TREES<<1, 3); |
908 | send_code(s, END_BLOCK, static_ltree); | 908 | send_code(s, END_BLOCK, static_ltree); |
909 | #ifdef DEBUG | 909 | #ifdef DEBUG |
910 | s->compressed_len += 10L; | 910 | s->compressed_len += 10L; |
911 | #endif | 911 | #endif |
912 | bi_flush(s); | 912 | bi_flush(s); |
913 | } | 913 | } |
914 | s->last_eob_len = 7; | 914 | s->last_eob_len = 7; |
915 | } | 915 | } |
916 | 916 | ||
917 | /* =========================================================================== | 917 | /* =========================================================================== |
918 | * Determine the best encoding for the current block: dynamic trees, static | 918 | * Determine the best encoding for the current block: dynamic trees, static |
919 | * trees or store, and output the encoded block to the zip file. | 919 | * trees or store, and output the encoded block to the zip file. |
920 | */ | 920 | */ |
921 | void _tr_flush_block(s, buf, stored_len, eof) | 921 | void _tr_flush_block(s, buf, stored_len, eof) |
922 | deflate_state *s; | 922 | deflate_state *s; |
923 | charf *buf; /* input block, or NULL if too old */ | 923 | charf *buf; /* input block, or NULL if too old */ |
924 | ulg stored_len; /* length of input block */ | 924 | ulg stored_len; /* length of input block */ |
925 | int eof; /* true if this is the last block for a file */ | 925 | int eof; /* true if this is the last block for a file */ |
926 | { | 926 | { |
927 | ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ | 927 | ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ |
928 | int max_blindex = 0; /* index of last bit length code of non zero freq */ | 928 | int max_blindex = 0; /* index of last bit length code of non zero freq */ |
929 | 929 | ||
930 | /* Build the Huffman trees unless a stored block is forced */ | 930 | /* Build the Huffman trees unless a stored block is forced */ |
931 | if (s->level > 0) { | 931 | if (s->level > 0) { |
932 | 932 | ||
933 | /* Check if the file is binary or text */ | 933 | /* Check if the file is binary or text */ |
934 | if (stored_len > 0 && s->strm->data_type == Z_UNKNOWN) | 934 | if (stored_len > 0 && s->strm->data_type == Z_UNKNOWN) |
935 | set_data_type(s); | 935 | set_data_type(s); |
936 | 936 | ||
937 | /* Construct the literal and distance trees */ | 937 | /* Construct the literal and distance trees */ |
938 | build_tree(s, (tree_desc *)(&(s->l_desc))); | 938 | build_tree(s, (tree_desc *)(&(s->l_desc))); |
939 | Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, | 939 | Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, |
940 | s->static_len)); | 940 | s->static_len)); |
941 | 941 | ||
942 | build_tree(s, (tree_desc *)(&(s->d_desc))); | 942 | build_tree(s, (tree_desc *)(&(s->d_desc))); |
943 | Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, | 943 | Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, |
944 | s->static_len)); | 944 | s->static_len)); |
945 | /* At this point, opt_len and static_len are the total bit lengths of | 945 | /* At this point, opt_len and static_len are the total bit lengths of |
946 | * the compressed block data, excluding the tree representations. | 946 | * the compressed block data, excluding the tree representations. |
947 | */ | 947 | */ |
948 | 948 | ||
949 | /* Build the bit length tree for the above two trees, and get the index | 949 | /* Build the bit length tree for the above two trees, and get the index |
950 | * in bl_order of the last bit length code to send. | 950 | * in bl_order of the last bit length code to send. |
951 | */ | 951 | */ |
952 | max_blindex = build_bl_tree(s); | 952 | max_blindex = build_bl_tree(s); |
953 | 953 | ||
954 | /* Determine the best encoding. Compute the block lengths in bytes. */ | 954 | /* Determine the best encoding. Compute the block lengths in bytes. */ |
955 | opt_lenb = (s->opt_len+3+7)>>3; | 955 | opt_lenb = (s->opt_len+3+7)>>3; |
956 | static_lenb = (s->static_len+3+7)>>3; | 956 | static_lenb = (s->static_len+3+7)>>3; |
957 | 957 | ||
958 | Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", | 958 | Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", |
959 | opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, | 959 | opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, |
960 | s->last_lit)); | 960 | s->last_lit)); |
961 | 961 | ||
962 | if (static_lenb <= opt_lenb) opt_lenb = static_lenb; | 962 | if (static_lenb <= opt_lenb) opt_lenb = static_lenb; |
963 | 963 | ||
964 | } else { | 964 | } else { |
965 | Assert(buf != (char*)0, "lost buf"); | 965 | Assert(buf != (char*)0, "lost buf"); |
966 | opt_lenb = static_lenb = stored_len + 5; /* force a stored block */ | 966 | opt_lenb = static_lenb = stored_len + 5; /* force a stored block */ |
967 | } | 967 | } |
968 | 968 | ||
969 | #ifdef FORCE_STORED | 969 | #ifdef FORCE_STORED |
970 | if (buf != (char*)0) { /* force stored block */ | 970 | if (buf != (char*)0) { /* force stored block */ |
971 | #else | 971 | #else |
972 | if (stored_len+4 <= opt_lenb && buf != (char*)0) { | 972 | if (stored_len+4 <= opt_lenb && buf != (char*)0) { |
973 | /* 4: two words for the lengths */ | 973 | /* 4: two words for the lengths */ |
974 | #endif | 974 | #endif |
975 | /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. | 975 | /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. |
976 | * Otherwise we can't have processed more than WSIZE input bytes since | 976 | * Otherwise we can't have processed more than WSIZE input bytes since |
977 | * the last block flush, because compression would have been | 977 | * the last block flush, because compression would have been |
978 | * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to | 978 | * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to |
979 | * transform a block into a stored block. | 979 | * transform a block into a stored block. |
980 | */ | 980 | */ |
981 | _tr_stored_block(s, buf, stored_len, eof); | 981 | _tr_stored_block(s, buf, stored_len, eof); |
982 | 982 | ||
983 | #ifdef FORCE_STATIC | 983 | #ifdef FORCE_STATIC |
984 | } else if (static_lenb >= 0) { /* force static trees */ | 984 | } else if (static_lenb >= 0) { /* force static trees */ |
985 | #else | 985 | #else |
986 | } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) { | 986 | } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) { |
987 | #endif | 987 | #endif |
988 | send_bits(s, (STATIC_TREES<<1)+eof, 3); | 988 | send_bits(s, (STATIC_TREES<<1)+eof, 3); |
989 | compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); | 989 | compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); |
990 | #ifdef DEBUG | 990 | #ifdef DEBUG |
991 | s->compressed_len += 3 + s->static_len; | 991 | s->compressed_len += 3 + s->static_len; |
992 | #endif | 992 | #endif |
993 | } else { | 993 | } else { |
994 | send_bits(s, (DYN_TREES<<1)+eof, 3); | 994 | send_bits(s, (DYN_TREES<<1)+eof, 3); |
995 | send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, | 995 | send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, |
996 | max_blindex+1); | 996 | max_blindex+1); |
997 | compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); | 997 | compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); |
998 | #ifdef DEBUG | 998 | #ifdef DEBUG |
999 | s->compressed_len += 3 + s->opt_len; | 999 | s->compressed_len += 3 + s->opt_len; |
1000 | #endif | 1000 | #endif |
1001 | } | 1001 | } |
1002 | Assert (s->compressed_len == s->bits_sent, "bad compressed size"); | 1002 | Assert (s->compressed_len == s->bits_sent, "bad compressed size"); |
1003 | /* The above check is made mod 2^32, for files larger than 512 MB | 1003 | /* The above check is made mod 2^32, for files larger than 512 MB |
1004 | * and uLong implemented on 32 bits. | 1004 | * and uLong implemented on 32 bits. |
1005 | */ | 1005 | */ |
1006 | init_block(s); | 1006 | init_block(s); |
1007 | 1007 | ||
1008 | if (eof) { | 1008 | if (eof) { |
1009 | bi_windup(s); | 1009 | bi_windup(s); |
1010 | #ifdef DEBUG | 1010 | #ifdef DEBUG |
1011 | s->compressed_len += 7; /* align on byte boundary */ | 1011 | s->compressed_len += 7; /* align on byte boundary */ |
1012 | #endif | 1012 | #endif |
1013 | } | 1013 | } |
1014 | Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, | 1014 | Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, |
1015 | s->compressed_len-7*eof)); | 1015 | s->compressed_len-7*eof)); |
1016 | } | 1016 | } |
1017 | 1017 | ||
1018 | /* =========================================================================== | 1018 | /* =========================================================================== |
1019 | * Save the match info and tally the frequency counts. Return true if | 1019 | * Save the match info and tally the frequency counts. Return true if |
1020 | * the current block must be flushed. | 1020 | * the current block must be flushed. |
1021 | */ | 1021 | */ |
1022 | int _tr_tally (s, dist, lc) | 1022 | int _tr_tally (s, dist, lc) |
1023 | deflate_state *s; | 1023 | deflate_state *s; |
1024 | unsigned dist; /* distance of matched string */ | 1024 | unsigned dist; /* distance of matched string */ |
1025 | unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ | 1025 | unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ |
1026 | { | 1026 | { |
1027 | s->d_buf[s->last_lit] = (ush)dist; | 1027 | s->d_buf[s->last_lit] = (ush)dist; |
1028 | s->l_buf[s->last_lit++] = (uch)lc; | 1028 | s->l_buf[s->last_lit++] = (uch)lc; |
1029 | if (dist == 0) { | 1029 | if (dist == 0) { |
1030 | /* lc is the unmatched char */ | 1030 | /* lc is the unmatched char */ |
1031 | s->dyn_ltree[lc].Freq++; | 1031 | s->dyn_ltree[lc].Freq++; |
1032 | } else { | 1032 | } else { |
1033 | s->matches++; | 1033 | s->matches++; |
1034 | /* Here, lc is the match length - MIN_MATCH */ | 1034 | /* Here, lc is the match length - MIN_MATCH */ |
1035 | dist--; /* dist = match distance - 1 */ | 1035 | dist--; /* dist = match distance - 1 */ |
1036 | Assert((ush)dist < (ush)MAX_DIST(s) && | 1036 | Assert((ush)dist < (ush)MAX_DIST(s) && |
1037 | (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && | 1037 | (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && |
1038 | (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match"); | 1038 | (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match"); |
1039 | 1039 | ||
1040 | s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++; | 1040 | s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++; |
1041 | s->dyn_dtree[d_code(dist)].Freq++; | 1041 | s->dyn_dtree[d_code(dist)].Freq++; |
1042 | } | 1042 | } |
1043 | 1043 | ||
1044 | #ifdef TRUNCATE_BLOCK | 1044 | #ifdef TRUNCATE_BLOCK |
1045 | /* Try to guess if it is profitable to stop the current block here */ | 1045 | /* Try to guess if it is profitable to stop the current block here */ |
1046 | if ((s->last_lit & 0x1fff) == 0 && s->level > 2) { | 1046 | if ((s->last_lit & 0x1fff) == 0 && s->level > 2) { |
1047 | /* Compute an upper bound for the compressed length */ | 1047 | /* Compute an upper bound for the compressed length */ |
1048 | ulg out_length = (ulg)s->last_lit*8L; | 1048 | ulg out_length = (ulg)s->last_lit*8L; |
1049 | ulg in_length = (ulg)((long)s->strstart - s->block_start); | 1049 | ulg in_length = (ulg)((long)s->strstart - s->block_start); |
1050 | int dcode; | 1050 | int dcode; |
1051 | for (dcode = 0; dcode < D_CODES; dcode++) { | 1051 | for (dcode = 0; dcode < D_CODES; dcode++) { |
1052 | out_length += (ulg)s->dyn_dtree[dcode].Freq * | 1052 | out_length += (ulg)s->dyn_dtree[dcode].Freq * |
1053 | (5L+extra_dbits[dcode]); | 1053 | (5L+extra_dbits[dcode]); |
1054 | } | 1054 | } |
1055 | out_length >>= 3; | 1055 | out_length >>= 3; |
1056 | Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", | 1056 | Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", |
1057 | s->last_lit, in_length, out_length, | 1057 | s->last_lit, in_length, out_length, |
1058 | 100L - out_length*100L/in_length)); | 1058 | 100L - out_length*100L/in_length)); |
1059 | if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; | 1059 | if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; |
1060 | } | 1060 | } |
1061 | #endif | 1061 | #endif |
1062 | return (s->last_lit == s->lit_bufsize-1); | 1062 | return (s->last_lit == s->lit_bufsize-1); |
1063 | /* We avoid equality with lit_bufsize because of wraparound at 64K | 1063 | /* We avoid equality with lit_bufsize because of wraparound at 64K |
1064 | * on 16 bit machines and because stored blocks are restricted to | 1064 | * on 16 bit machines and because stored blocks are restricted to |
1065 | * 64K-1 bytes. | 1065 | * 64K-1 bytes. |
1066 | */ | 1066 | */ |
1067 | } | 1067 | } |
1068 | 1068 | ||
1069 | /* =========================================================================== | 1069 | /* =========================================================================== |
1070 | * Send the block data compressed using the given Huffman trees | 1070 | * Send the block data compressed using the given Huffman trees |
1071 | */ | 1071 | */ |
1072 | local void compress_block(s, ltree, dtree) | 1072 | local void compress_block(s, ltree, dtree) |
1073 | deflate_state *s; | 1073 | deflate_state *s; |
1074 | ct_data *ltree; /* literal tree */ | 1074 | ct_data *ltree; /* literal tree */ |
1075 | ct_data *dtree; /* distance tree */ | 1075 | ct_data *dtree; /* distance tree */ |
1076 | { | 1076 | { |
1077 | unsigned dist; /* distance of matched string */ | 1077 | unsigned dist; /* distance of matched string */ |
1078 | int lc; /* match length or unmatched char (if dist == 0) */ | 1078 | int lc; /* match length or unmatched char (if dist == 0) */ |
1079 | unsigned lx = 0; /* running index in l_buf */ | 1079 | unsigned lx = 0; /* running index in l_buf */ |
1080 | unsigned code; /* the code to send */ | 1080 | unsigned code; /* the code to send */ |
1081 | int extra; /* number of extra bits to send */ | 1081 | int extra; /* number of extra bits to send */ |
1082 | 1082 | ||
1083 | if (s->last_lit != 0) do { | 1083 | if (s->last_lit != 0) do { |
1084 | dist = s->d_buf[lx]; | 1084 | dist = s->d_buf[lx]; |
1085 | lc = s->l_buf[lx++]; | 1085 | lc = s->l_buf[lx++]; |
1086 | if (dist == 0) { | 1086 | if (dist == 0) { |
1087 | send_code(s, lc, ltree); /* send a literal byte */ | 1087 | send_code(s, lc, ltree); /* send a literal byte */ |
1088 | Tracecv(isgraph(lc), (stderr," '%c' ", lc)); | 1088 | Tracecv(isgraph(lc), (stderr," '%c' ", lc)); |
1089 | } else { | 1089 | } else { |
1090 | /* Here, lc is the match length - MIN_MATCH */ | 1090 | /* Here, lc is the match length - MIN_MATCH */ |
1091 | code = _length_code[lc]; | 1091 | code = _length_code[lc]; |
1092 | send_code(s, code+LITERALS+1, ltree); /* send the length code */ | 1092 | send_code(s, code+LITERALS+1, ltree); /* send the length code */ |
1093 | extra = extra_lbits[code]; | 1093 | extra = extra_lbits[code]; |
1094 | if (extra != 0) { | 1094 | if (extra != 0) { |
1095 | lc -= base_length[code]; | 1095 | lc -= base_length[code]; |
1096 | send_bits(s, lc, extra); /* send the extra length bits */ | 1096 | send_bits(s, lc, extra); /* send the extra length bits */ |
1097 | } | 1097 | } |
1098 | dist--; /* dist is now the match distance - 1 */ | 1098 | dist--; /* dist is now the match distance - 1 */ |
1099 | code = d_code(dist); | 1099 | code = d_code(dist); |
1100 | Assert (code < D_CODES, "bad d_code"); | 1100 | Assert (code < D_CODES, "bad d_code"); |
1101 | 1101 | ||
1102 | send_code(s, code, dtree); /* send the distance code */ | 1102 | send_code(s, code, dtree); /* send the distance code */ |
1103 | extra = extra_dbits[code]; | 1103 | extra = extra_dbits[code]; |
1104 | if (extra != 0) { | 1104 | if (extra != 0) { |
1105 | dist -= base_dist[code]; | 1105 | dist -= base_dist[code]; |
1106 | send_bits(s, dist, extra); /* send the extra distance bits */ | 1106 | send_bits(s, dist, extra); /* send the extra distance bits */ |
1107 | } | 1107 | } |
1108 | } /* literal or match pair ? */ | 1108 | } /* literal or match pair ? */ |
1109 | 1109 | ||
1110 | /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ | 1110 | /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ |
1111 | Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx, | 1111 | Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx, |
1112 | "pendingBuf overflow"); | 1112 | "pendingBuf overflow"); |
1113 | 1113 | ||
1114 | } while (lx < s->last_lit); | 1114 | } while (lx < s->last_lit); |
1115 | 1115 | ||
1116 | send_code(s, END_BLOCK, ltree); | 1116 | send_code(s, END_BLOCK, ltree); |
1117 | s->last_eob_len = ltree[END_BLOCK].Len; | 1117 | s->last_eob_len = ltree[END_BLOCK].Len; |
1118 | } | 1118 | } |
1119 | 1119 | ||
1120 | /* =========================================================================== | 1120 | /* =========================================================================== |
1121 | * Set the data type to BINARY or TEXT, using a crude approximation: | 1121 | * Set the data type to BINARY or TEXT, using a crude approximation: |
1122 | * set it to Z_TEXT if all symbols are either printable characters (33 to 255) | 1122 | * set it to Z_TEXT if all symbols are either printable characters (33 to 255) |
1123 | * or white spaces (9 to 13, or 32); or set it to Z_BINARY otherwise. | 1123 | * or white spaces (9 to 13, or 32); or set it to Z_BINARY otherwise. |
1124 | * IN assertion: the fields Freq of dyn_ltree are set. | 1124 | * IN assertion: the fields Freq of dyn_ltree are set. |
1125 | */ | 1125 | */ |
1126 | local void set_data_type(s) | 1126 | local void set_data_type(s) |
1127 | deflate_state *s; | 1127 | deflate_state *s; |
1128 | { | 1128 | { |
1129 | int n; | 1129 | int n; |
1130 | 1130 | ||
1131 | for (n = 0; n < 9; n++) | 1131 | for (n = 0; n < 9; n++) |
1132 | if (s->dyn_ltree[n].Freq != 0) | 1132 | if (s->dyn_ltree[n].Freq != 0) |
1133 | break; | 1133 | break; |
1134 | if (n == 9) | 1134 | if (n == 9) |
1135 | for (n = 14; n < 32; n++) | 1135 | for (n = 14; n < 32; n++) |
1136 | if (s->dyn_ltree[n].Freq != 0) | 1136 | if (s->dyn_ltree[n].Freq != 0) |
1137 | break; | 1137 | break; |
1138 | s->strm->data_type = (n == 32) ? Z_TEXT : Z_BINARY; | 1138 | s->strm->data_type = (n == 32) ? Z_TEXT : Z_BINARY; |
1139 | } | 1139 | } |
1140 | 1140 | ||
1141 | /* =========================================================================== | 1141 | /* =========================================================================== |
1142 | * Reverse the first len bits of a code, using straightforward code (a faster | 1142 | * Reverse the first len bits of a code, using straightforward code (a faster |
1143 | * method would use a table) | 1143 | * method would use a table) |
1144 | * IN assertion: 1 <= len <= 15 | 1144 | * IN assertion: 1 <= len <= 15 |
1145 | */ | 1145 | */ |
1146 | local unsigned bi_reverse(code, len) | 1146 | local unsigned bi_reverse(code, len) |
1147 | unsigned code; /* the value to invert */ | 1147 | unsigned code; /* the value to invert */ |
1148 | int len; /* its bit length */ | 1148 | int len; /* its bit length */ |
1149 | { | 1149 | { |
1150 | register unsigned res = 0; | 1150 | register unsigned res = 0; |
1151 | do { | 1151 | do { |
1152 | res |= code & 1; | 1152 | res |= code & 1; |
1153 | code >>= 1, res <<= 1; | 1153 | code >>= 1, res <<= 1; |
1154 | } while (--len > 0); | 1154 | } while (--len > 0); |
1155 | return res >> 1; | 1155 | return res >> 1; |
1156 | } | 1156 | } |
1157 | 1157 | ||
1158 | /* =========================================================================== | 1158 | /* =========================================================================== |
1159 | * Flush the bit buffer, keeping at most 7 bits in it. | 1159 | * Flush the bit buffer, keeping at most 7 bits in it. |
1160 | */ | 1160 | */ |
1161 | local void bi_flush(s) | 1161 | local void bi_flush(s) |
1162 | deflate_state *s; | 1162 | deflate_state *s; |
1163 | { | 1163 | { |
1164 | if (s->bi_valid == 16) { | 1164 | if (s->bi_valid == 16) { |
1165 | put_short(s, s->bi_buf); | 1165 | put_short(s, s->bi_buf); |
1166 | s->bi_buf = 0; | 1166 | s->bi_buf = 0; |
1167 | s->bi_valid = 0; | 1167 | s->bi_valid = 0; |
1168 | } else if (s->bi_valid >= 8) { | 1168 | } else if (s->bi_valid >= 8) { |
1169 | put_byte(s, (Byte)s->bi_buf); | 1169 | put_byte(s, (Byte)s->bi_buf); |
1170 | s->bi_buf >>= 8; | 1170 | s->bi_buf >>= 8; |
1171 | s->bi_valid -= 8; | 1171 | s->bi_valid -= 8; |
1172 | } | 1172 | } |
1173 | } | 1173 | } |
1174 | 1174 | ||
1175 | /* =========================================================================== | 1175 | /* =========================================================================== |
1176 | * Flush the bit buffer and align the output on a byte boundary | 1176 | * Flush the bit buffer and align the output on a byte boundary |
1177 | */ | 1177 | */ |
1178 | local void bi_windup(s) | 1178 | local void bi_windup(s) |
1179 | deflate_state *s; | 1179 | deflate_state *s; |
1180 | { | 1180 | { |
1181 | if (s->bi_valid > 8) { | 1181 | if (s->bi_valid > 8) { |
1182 | put_short(s, s->bi_buf); | 1182 | put_short(s, s->bi_buf); |
1183 | } else if (s->bi_valid > 0) { | 1183 | } else if (s->bi_valid > 0) { |
1184 | put_byte(s, (Byte)s->bi_buf); | 1184 | put_byte(s, (Byte)s->bi_buf); |
1185 | } | 1185 | } |
1186 | s->bi_buf = 0; | 1186 | s->bi_buf = 0; |
1187 | s->bi_valid = 0; | 1187 | s->bi_valid = 0; |
1188 | #ifdef DEBUG | 1188 | #ifdef DEBUG |
1189 | s->bits_sent = (s->bits_sent+7) & ~7; | 1189 | s->bits_sent = (s->bits_sent+7) & ~7; |
1190 | #endif | 1190 | #endif |
1191 | } | 1191 | } |
1192 | 1192 | ||
1193 | /* =========================================================================== | 1193 | /* =========================================================================== |
1194 | * Copy a stored block, storing first the length and its | 1194 | * Copy a stored block, storing first the length and its |
1195 | * one's complement if requested. | 1195 | * one's complement if requested. |
1196 | */ | 1196 | */ |
1197 | local void copy_block(s, buf, len, header) | 1197 | local void copy_block(s, buf, len, header) |
1198 | deflate_state *s; | 1198 | deflate_state *s; |
1199 | charf *buf; /* the input data */ | 1199 | charf *buf; /* the input data */ |
1200 | unsigned len; /* its length */ | 1200 | unsigned len; /* its length */ |
1201 | int header; /* true if block header must be written */ | 1201 | int header; /* true if block header must be written */ |
1202 | { | 1202 | { |
1203 | bi_windup(s); /* align on byte boundary */ | 1203 | bi_windup(s); /* align on byte boundary */ |
1204 | s->last_eob_len = 8; /* enough lookahead for inflate */ | 1204 | s->last_eob_len = 8; /* enough lookahead for inflate */ |
1205 | 1205 | ||
1206 | if (header) { | 1206 | if (header) { |
1207 | put_short(s, (ush)len); | 1207 | put_short(s, (ush)len); |
1208 | put_short(s, (ush)~len); | 1208 | put_short(s, (ush)~len); |
1209 | #ifdef DEBUG | 1209 | #ifdef DEBUG |
1210 | s->bits_sent += 2*16; | 1210 | s->bits_sent += 2*16; |
1211 | #endif | 1211 | #endif |
1212 | } | 1212 | } |
1213 | #ifdef DEBUG | 1213 | #ifdef DEBUG |
1214 | s->bits_sent += (ulg)len<<3; | 1214 | s->bits_sent += (ulg)len<<3; |
1215 | #endif | 1215 | #endif |
1216 | while (len--) { | 1216 | while (len--) { |
1217 | put_byte(s, *buf++); | 1217 | put_byte(s, *buf++); |
1218 | } | 1218 | } |
1219 | } | 1219 | } |